WO2020193096A1

WO2020193096A1 - Drive device for a diaphragm wall cutter

Info

Publication number: WO2020193096A1
Application number: PCT/EP2020/055789
Authority: WO
Inventors: Roland Widmann; Johannes HALDER; Stefan Duelli
Original assignee: Liebherr-Components Biberach Gmbh
Priority date: 2019-03-25
Filing date: 2020-03-05
Publication date: 2020-10-01
Also published as: US20220056661A1; JP7411675B2; JP2022526883A

Abstract

The invention relates to a drive device for a diaphragm wall cutter (1), with a hydraulic motor (8), a gear unit (9), to which at least one cutting wheel (3) of the diaphragm wall cutter can be connected on the output side, and a drive shaft (12) which connects the hydraulic motor to the gear unit, wherein the drive shaft is mounted by way of at least one drive shaft bearing (25) which is arranged between the hydraulic motor and the gear unit, wherein the drive shaft bearing has a lubricant feed line (14) which is connected to a leakage discharge line of the hydraulic motor and/or to the hydraulic circuit in order to operate the hydraulic motor, and is configured to lubricate the drive shaft bearing with hydraulic oil.

Description

Drive device for a trench wall cutter

The present invention relates to a drive device for a Schlitzwandfrä se, with a hydraulic motor, a gearbox to which at least one cutting wheel of the trench cutter can be connected on the output side, and a drive shaft that connects the hydraulic motor to the gearbox, the drive shaft being supported by at least one drive shaft bearing which is arranged between the hydraulic motor and the transmission. The invention also relates to a trench wall cutter with such a drive device.

Diaphragm wall cutters are usually used in special civil engineering to mill slots in the ground, rock or subsurface, which are filled with a suspension containing, for example, concrete to form a diaphragm wall. Such slit walls are generally wall constructions in the subsoil made of, for example, concrete, reinforced concrete and the like, in order to seal, support or generally influence the subsoil in a certain way. In order to produce such a trench wall, a trench wall cutter is used to cut a substantially vertical, upwardly open slot, the cutting tool being lowered into the ground from above and guided by a preferably movable carrier device such as a crawler rope excavator supported on the ground . The Trench wall cutter usually comprises an elongated, upright milling frame, which is suspended vertically movable on the carrier device and at its lower end usually carries several milling wheels that can be driven in opposite directions about axes lying in each case. The drive for rotationally driving the Fräsrä the can also be mounted on a lower portion of the milling frame and include, for example, one or more Flydromotors that can drive the milling wheels via one or more gear stages.

The excavated soil material can be pumped to the surface of the earth using an overburden pump, while the slot is constantly stabilized with a support suspension so that the slot or the diaphragm walls do not collapse. After reaching the required depth, the slot is then usually concreted.

By spacing the hydraulic motor from the gearbox, which is achieved by the drive shaft mentioned, a compact design can be achieved. In particular, space problems on the end shield can be avoided if it is made narrow in the desired manner. In particular, the hydraulic motor can be arranged above the bearing plate, where the cutting wheels are rotatably mounted so that the overall depth in the area of the cutting wheels can be kept small.

However, with such a spacing and arrangement of the hydraulic motor, lubrication problems arise. While the main components of the gearbox, in particular its planetary gears, sun gear and planet carrier, can be lubricated with oil sump lubrication in the area of the gearbox housing, the drive shaft bearing, which supports the drive shaft between the hydraulic motor and the gearbox, is outside the gearbox housing or no longer in the area the oil sump and its spray width, so that the lubrication of the drive shaft bearing is a challenge.

One solution is to use a permanently lubricated bearing for the drive shaft bearing. Another approach is to use a separate fat or to install oil lubrication in order to continuously or cyclically supply grease and / or oil to the drive shaft bearing and the connection of the drive shaft to the motor shaft. Both approaches, however, entail increased maintenance costs, since the permanently lubricated bearing and also the seals and nipples of a grease lubrication system must be checked regularly and then replaced. This increases the operating costs, while the effective operating time of the trench wall cutter is reduced accordingly.

Furthermore, the document EP 16 37 794 B1 proposes to promote the transmission oil located in the bottom pan of the Ge transmission over the rotating drive shaft up to the drive shaft bearing. For this purpose, the drive shaft is provided with a kind of Förderge thread, which promotes the oil upwards in the manner of a worm shaft and thereby lubricates the drive shaft bearing and the toothing between the drive shaft and the motor shaft. However, this approach is not only disadvantageous with regard to the increased production costs for the drive shaft, but above all includes the problem that lubrication of the drive shaft bearing is only achieved when the drive shaft is operating in the “correct” direction of rotation. If the direction of rotation is reversed, exactly the opposite is achieved and the oil is pumped downwards. Apart from this, the promotion of the transmission oil upwards to the drive shafts only begins when the transmission or the drive shaft starts to run, which at least when starting up leads to a brief lack of lubrication of the drive shaft bearings. Longer downtimes worsen the oil supply as the oil settles down.

Proceeding from this, the present invention is based on the object of creating an improved drive device for a trench wall cutter and an improved trench wall cutter that avoid the disadvantages of the prior art and further develop the latter in an advantageous manner. In particular, permanent lubrication of the drive shaft bearing between the hydraulic motor and gearbox is to be achieved without increased maintenance effort, which functions independently of the direction of rotation of the drive and does not show any start-up problems. According to the invention, the above object is achieved by a drive device according to claim 1 and a trench wall cutter according to claim 17. Before ferred refinements of the invention are the subject of the dependent claims.

It is therefore proposed not to lubricate the drive shaft bearing or at least not primarily through the transmission oil, but instead to use hydraulic oil with which the hydraulic motor is operated. According to the invention, the drive shaft bearing has a lubricant inlet which supplies the drive shaft bearing with leakage oil from the hydraulic motor and / or hydraulic oil from the hydraulic circuit for operating the hydraulic motor. At least part of the leakage oil of the hydraulic motor and / or part of the hydraulic oil from the hydraulic circuit is passed through the drive shaft bearing to be lubricated and / or to other components of the drive train to be lubricated between the hydraulic motor and the transmission to the drive bearing or the aforementioned to lubricate other components.

In an advantageous development of the invention, for the lubrication of the drive shaft bearing and / or the connection between the drive shaft and the hydraulic motor, a leakage of the hydraulic motor can be deliberately brought about and / or increased, for example by omitting a shaft seal on the hydraulic motor and / or a specially provided leakage hole through the Motor housing and / or is passed through the motor shaft in order to lead leakage oil to the drive shaft bearing and / or connection.

Said lubricant inlet of the drive shaft bearing can have a leakage collector or a leakage collective inlet, which engages around and / or underneath the motor shaft of the hydraulic motor and / or the outlet area in which the motor shaft emerges from the motor housing of the hydraulic motor, so that leakage oil enters the named leakage collective inlet drips or splashes. Such a leakage collective inlet can be particularly advantageous when the hydraulic motor is arranged above the drive shaft and faces the drive shaft with its motor shaft pointing downwards. Said hydraulic motor can be arranged upside down, so to speak, and positioned upright over the drive shaft, wherein the motor shaft of the hydraulic motor can in particular be arranged coaxially to the drive shaft.

As an alternative or in addition to a leakage feed, the lubricant feed of the drive shaft bearing can also have a fresh oil feed that can be connected to a section of the hydraulic circuit upstream of the hydraulic motor in order to supply fresh hydraulic oil that has not yet been hydraulically and by the work to be performed in the hydraulic motor / or is thermally stressed or consumed, to be used to lubricate the drive shaft bearings. Hydraulic oil can be tapped, so to speak, via such a fresh oil inlet, which oil would have been intended to flow into the hydraulic motor in order to drive said hydraulic motor. While the leakage oil that emerges from the hydraulic motor after the work is done is usually hot or thermally stressed, Fri schöl, which was branched off from the hydraulic circuit upstream of the hydraulic motor, usually has a significantly cooler temperature. The hydraulic oil, which is not designed to lubricate the drive shaft bearing, can generate a better lubricating film at cooler temperatures and accordingly achieve better lubricating performance. In addition, the drive shaft bearing is cooled.

In a further development of the invention, the at least one drive shaft bearing can comprise a bearing sleeve or a housing, within which a coupling sleeve can be rotatably mounted, which coupling sleeve non-rotatably connects the drive shaft to the motor shaft of the hydraulic motor. Said coupling sleeve and / or the drive shaft can be supported radially and / or axially on an inner circumferential surface of said bearing sleeve by rotary bearings, for example roller bearings and / or plain bearings, so that the housing or said bearing sleeve accommodates the coupling sleeve and / or the inside the drive shaft extending into the bearing sleeve is rotatably supported. At the same time, said bearing sleeve and / or said coupling sleeve can take on a lubricating function and / or form part of said lubricant inlet via which hydraulic oil is supplied to lubricate the drive shaft bearing and / or the connection between drive shaft and motor shaft.

In particular, said coupling sleeve can be formed oil-tight towards the drive shaft so that an interior of the coupling sleeve forms an oil collecting space and oil in the interior of the coupling sleeve cannot easily run off to the drive shaft. Such a tight design of the coupling sleeve towards the drive shaft can be achieved, for example, in that the coupling sleeve is molded onto the drive shaft in one piece with homogeneous material.

However, in order to be able to detach the coupling sleeve from the drive shaft, which considerably simplifies assembly and maintenance, but on the other hand still achieves a sealing formation, a seal can be provided between the coupling sleeve and the drive shaft to seal the interior of the coupling sleeve from the drive shaft .

Said coupling sleeve can advantageously encompass the motor shaft of the hydraulic motor or the motor shaft stub emerging from the motor housing in a cup-like manner, so that leakage oil leaking from the motor shaft stub runs into said coupling sleeve and is collected there, whereby the connection or the engagement surfaces between the coupling sleeve and the motor shaft or between the coupling sleeve and the drive shaft.

In a further development of the invention, a non-rotatable connection between the coupling sleeve and the motor shaft and / or between the coupling sleeve and the drive shaft can be achieved by positive-locking connection means, for example a splined shaft profile and / or a polygon profile or a shaft-hub- connection. The mentioned lubricant feed of the The drive shaft bearing can supply hydraulic oil as a lubricant, in particular leakage oil from the hydraulic motor, to the engagement surfaces of said rotationally fixed connec tion medium.

As an alternative or in addition to using the coupling sleeve as a lubricant distributor, the aforementioned bearing sleeve, in which the coupling sleeve is rotatably mounted, can also be used as part of the lubricant inlet in order to supply hydraulic oil to the lubricating elements. In particular, the named bearing sleeve can be connected with one end face to the motor housing of the hydraulic motor and / or encompass the motor shaft emerging therefrom.

Advantageously, said bearing sleeve can be sealed off from the coupling sleeve and / or towards the drive shaft by a rotary seal, so that an interior of the said bearing sleeve forms a collecting space for hydraulic oil and / or hydraulic oil fed into the interior of the bearing sleeve cannot easily run off to the drive shaft .

Independently of this, said bearing sleeve can form a vertically mounted component which does not rotate.

Said bearing sleeve can, on the one hand, collect leakage oil emerging from the motor shaft or leakage oil splashed from the motor shaft. Independently of this, the bearing sleeve mentioned can also serve to supply hydraulic oil or fresh oil branched off upstream of the hydraulic motor to the drive shaft bearing and / or the connecting elements between the drive shaft and the motor shaft.

In an advantageous development of the invention, the fresh oil inlet, which can be connected to a section of the hydraulic circuit upstream of the hydraulic motor, can lead into the interior of the bearing sleeve mentioned, in particular into the space between the bearing sleeve and the coupling sleeve. Advantageously, the said fresh oil supply can be back through a wall of the said bearing sleeve. perform so that the fresh oil can be fed into the interior of the bearing sleeve through the bearing sleeve wall.

Said fresh oil inlet can in particular lead through an edge section of the bearing sleeve, which is connected to the hydraulic motor, so that the fresh oil is guided very close to the hydraulic motor into the interior of the bearing sleeve.

Advantageously, the leakage oil and / or the fresh oil branched off upstream of the hydraulic motor can be fed through essentially the entire length of the bearing sleeve and / or returned to the hydraulic circuit for operating the hydraulic motor after passing through the bearing sleeve.

In particular, the named bearing sleeve can have a hydraulic oil drain, which can be arranged at an opposite end section to the hydraulic oil inlet, in particular to the named fresh oil inlet. If the said fresh oil supply is provided in the aforementioned manner on the edge section of the bearing sleeve attached to the hydraulic motor, the hydraulic oil drain can be provided on an opposite edge section of the bearing sleeve facing away from the hydraulic motor.

In particular, said bearing sleeve can have a fresh oil inlet on an upper sleeve section and a hydraulic oil outlet on a lower Lagerhülsenab section.

Advantageously, lubrication of the rolling bearings and / or plain bearings can be achieved through said bearing sleeve, while lubrication of the toothing or engagement surfaces for transmitting the torque of the hydraulic motor to the drive shaft is advantageously seen through said coupling sleeve. In a further development of the invention, an oil collection chamber can be provided below the drive shaft bearing and / or below the non-rotatable connection between the motor shaft and drive shaft in order to collect hydraulic oil that has been used to lubricate the drive shaft bearing and / or the non-rotatable connection through any leaks. This makes tightness control considerably easier, since the oil level in said collecting chamber is an indicator of the tightness.

Advantageously, the named chamber can be assigned an oil level sensor which detects the oil level of the hydraulic oil collected in the collecting chamber and can output a corresponding oil level signal.

A closable drain can be assigned to said collecting chamber in order to be able to drain oil collected at regular intervals or also to be able to check whether oil is leaking out and arriving in said collecting chamber. If no oil emerges from the collection chamber when the outlet is opened, it can be concluded that there are no leaks.

Said collection chamber can advantageously be designed to be open to the gearbox or also to be open. In order to prevent hydraulic oil from leaking into the transmission and, accordingly, mixing of hydraulic oil and transmission oil, even when the design is open, the aforementioned collection chamber can have a riser pipe through which the drive shaft can extend. Alternatively or in addition, said collecting chamber can also be sealed against the drive shaft and / or the transmission by a seal.

The invention is explained in more detail below with the aid of a preferred exemplary embodiment and associated drawings. In the drawings show:

1: a schematic, perspective illustration of a trench wall cutter according to an advantageous embodiment of the invention, 2: a perspective view of the drive device for the cutting wheels of the trench wall cutter from FIG. 1, the drive motor being mounted on an upper section of a bearing plate and the gear housing, on which the cutting wheels of the trench wall cutter from FIG. 1 are attached,

Fig. 3: a longitudinal section through the drive device for driving the

Milling wheels of the trench wall cutter from the previous figures, which shows the drive shaft between the milling gear and the hydraulic motor and the drive shaft bearing between the hydraulic motor and the transmission and the non-rotatable connection between the drive shaft and the hydraulic motor shaft, and

4: an enlarged longitudinal section through the drive shaft bearing and the non-rotatable connection between drive shaft and motor shaft.

As FIG. 1 shows, a trench wall cutter 1 can have an elongated, uprightly arranged milling frame 2, which can be designed as a girder and / or can include two laterally arranged longitudinal guide profiles. At a lower end section, the milling frame 2 can have at least two milling wheels 3, which are arranged side by side and can be rotatably driven about the respective lying axes of rotation, the axes of rotation of the milling wheels 3 zueinan extending parallel and / or perpendicular to the flat side of the milling frame 2 nen.

The milling wheels 3 can be driven in opposite directions to one another. A Fräsan drive 4 can be arranged at a lower end portion of the milling section 2 above the milling wheels 3 and include one or more drive motors 8, for example in the form of hydraulic motors that can drive the milling wheels 3 via a gear or one or more gear stages 9. As FIG. 1 shows, the milling frame 2 with the milling wheels 3 can be held by a support device 5 such that it can be raised and lowered or suspended from it. The ge called carrier device 5 stands on the ground, in which the respective slot milled who should, and can advantageously be moved. In particular, a rope excavator with a chassis, for example in the form of a Ket chassis 6, can be provided as Trä gergerät 5, wherein the milling frame 2 can be raised and lowered by a boom 7 of the carrier 5.

As FIGS. 2 to 4 show, the milling wheel drive 4 can be arranged on a bearing plate 10 or comprise such a bearing plate 10 by means of which the drive device can be fastened to the mentioned milling frame 2. For example, said bearing plate 10 can be a T-shaped carrier, which can be attached with its upper portion to the milling frame 2 and on its lower portion can carry a drive and / or gear housing 11, in wel chem said gear stage 9 at least partially is recorded.

The drive motor 8 can, for example, be fastened to the upper end of the end shield 10 and be coupled to the gear stage 9 in a driving manner via a drive shaft 12, which can extend inside the end shield 10. Said gear stage 9 can include one or more planetary gear stages in order to drive one of the mentioned milling wheels 3.

As FIG. 3 shows, the two planetary gears 9, via which the cutting wheels 3 are driven, can be drive-connected to the hydraulic motor 8 by an essentially upright drive shaft 12, which can be arranged above the gear 9 on the bearing plate 10. Said hydraulic motor 8 can be arranged plunged down with its motor shaft stub 16 protruding from the motor housing 17, preferably coaxially to the drive shaft 12 mentioned. The hydraulic motor 8 can be arranged vertically with its motor shaft 16 and positioned pointing downwards . As Figure 4 shows, the motor shaft 16 of the hydraulic motor 8 can be rotatably connected to the drive shaft 12 by a coupling sleeve 21, whereby the coupling sleeve 21 can sit on the one hand in a cup-like manner on the motor shaft 16 and on the other hand in a cup-like manner on the drive shaft 12. The non-rotatable connecting means between coupling sleeve 21 and motor shaft 16 or coupling sleeve 21 and to drive shaft 12 can include, for example, a splined shaft profile, a toothing or a polygonal profile.

Said coupling sleeve 21 can advantageously be rotatably supported by roller bearings 25, alternatively or additionally also by sliding bearings on a bearing sleeve 20 which surrounds or can accommodate said coupling sleeve 21. Said bearing sleeve 20 can be arranged stationary, insbesonde re be mounted on the bearing plate 10 and connect or carry the hydraulic motor 8. In particular, the bearing sleeve 20 can encompass the motor shaft 16 and be connected or fastened at the end to the motor housing 17 of the hydraulic motor 8 in order to mount the hydraulic motor 8. The end face of the bearing sleeve 20 can be fastened to the bearing plate 10.

In order to lubricate the engagement surfaces between the coupling sleeve and drive shaft 12 or coupling sleeve 21 and motor shaft 16, the interior of the coupling sleeve 21 can form part of a lubricant inlet 14 to prevent leakage oil from the hydraulic motor 8 and / or separately into the interior of the La to lead gerhülse 20 supplied fresh oil to said engagement surfaces. In particular, the interior of the coupling sleeve 21 can form a leakage collecting inlet 18, which can collect leaking oil at the motor shaft 16 or the interface between the motor shaft 16 and motor housing 17 and guide it to the aforementioned engagement surfaces. In order to lead sufficient leakage oil to the upwardly open interior of the coupling sleeve 21, a shaft seal can be dispensed with on the hydraulic motor 8, which would normally seal the motor shaft 16 against the motor housing 17, so that by omitting the shaft seal at the outlet of the motor shaft 16 leakage oil exits into the coupling treatment sleeve 21 enters, in particular at its upwardly open end, which surrounds the motor shaft 16 like a cup.

To prevent the leakage oil from escaping unintentionally at the lower end of the coupling sleeve 21, a seal 22 can be provided at the lower end or end portion of the coupling sleeve 21, which seals the coupling sleeve 21 with respect to the drive shaft 12. Said seal 22 can seal the gap that is provided circumferentially between drive shaft 12 and coupling sleeve 21, in particular in a shaft section that adjoins the non-rotatable profiling of drive shaft 12 or is below this non-rotatable connecting section.

In order to not only supply the lubrication points located inside the coupling sleeve 21 with hydraulic oil, but also the aforementioned roller bearings 25, which are provided between the coupling sleeve 21 and bearing sleeve 20, the aforementioned leakage oil that escapes from the hydraulic motor 8 can also be used which can be sprayed by the rotating motor shaft 16, especially if the coupling sleeve 21 does not completely enclose the motor shaft 16 up to the motor housing 17.

Alternatively or in addition to the leakage oil mentioned, fresh oil can also be fed into the gap between the bearing sleeve 20 and the coupling sleeve 21, which is branched off from the hydraulic circuit 15 upstream of the hydraulic motor 8, by means of which the hydraulic motor 8 is driven.

Advantageously, the bearing sleeve 20 can have a fresh oil inlet 19, which can extend at the upper end of the bearing sleeve 20 immediately adjacent to the Motorgehäu se 17 through the wall of the bearing sleeve 20, see. FIG. 4. By supplying fresh oil to the upper end section of the bearing sleeve 20 into the interior of the bearing sleeve 20, this fresh oil can run downwards, dripped by gravity, or drip or splash in order to lubricate the bearings 25. Advantageously, a lower end portion of the bearing sleeve 20 can be sealed by a rotary seal 23 with respect to the drive shaft 12 and / or with respect to the coupling sleeve 21, so that the annular interior space between the bearing sleeve 20 and coupling sleeve 21 or drive shaft 12 is sealed at the bottom, in order to prevent hydraulic oil from running into the transmission 9 and mixing with the transmission oil there.

Said seal 22 in particular in the form of a rotary seal for sealing from the bearing sleeve 20 can advantageously be arranged below all bearings 25.

As FIG. 4 shows, a collecting chamber 24 can advantageously be provided below the bearing and coupling sleeves 20 and 21, in particular also below the seal 22 and / or the rotary seal 23, which is formed around the drive shaft 12 or through which the drive shaft 12 passes. Said collecting chamber 24 can be formed in the end shield 10, for example. A riser pipe 26 can advantageously delimit the collecting chamber 24 and extend around the drive shaft 12 or form an elevation there, in order to prevent hydraulic oil collected in the collecting chamber 24 from running down the drive shaft 12 into the transmission 9.

Said collecting chamber 24 can have an outlet 27, which can advantageously be provided with a releasable closure 28 in order to be able to open the outlet 27. Said drain 27 is preferably designed in such a way that hydraulic oil, which may be located in the collecting chamber 24, can drain away driven by gravity. The drain 27 can, for example, start at the bottom of the collecting chamber 24 and possibly posses a certain gradient in order to allow oil to drain off.

By opening the closure 28 it can be checked whether the seals 22 or 23 are leaking and whether there is oil in the collection chamber 24. Alternatively or additionally, the presence of oil in the collecting chamber 24 can also be checked by an oil level sensor system 29, by means of which the filling level in the collecting chamber 24 can be sensed in order to emit a corresponding oil level signal, for example to provide a machine control system. On the basis of the oil level in the collecting chamber 24, a maintenance signal can be issued or a maintenance process can be initiated.

Claims

1. Drive device for a trench cutter, with a hydraulic motor (8), a gear (9) to which at least one cutting wheel (3) of the trench cutter (1) can be connected on the output side, as well as a drive shaft (12) that drives the hydraulic motor (8) connects to the gearbox (9), the drive shaft (12) being supported by at least one drive shaft bearing (13) which is arranged between the hydraulic motor (8) and the gearbox (9), characterized in that the drive shaft bearing (13) has a lubricant inlet (14) which is closed to a leakage outlet of the hydraulic motor (8) and / or the hydraulic circuit (15) for operating the hydraulic motor (8) and is designed to lubricate the drive shaft bearing (13) with lubricant.

2. Drive device according to the preceding claim, wherein the hydrau likmotor (8) at the exit of the motor shaft (16) from the motor housing (17) is formed without a seal and the lubricant inlet (14) has a lever ckage collective inlet (18) which engages around and / or under the motor shaft (16) and / or its exit from the motor housing (17).

3. Drive device according to one of the preceding claims, wherein the hydraulic motor (8) is arranged above the drive shaft (12) and with its motor shaft (16) facing downward facing the drive shaft (12), in particular standing upright overhead coaxially to the drive shaft le (12) is aligned.

4. Drive device according to one of the preceding claims, wherein the lubricant inlet (14) has a fresh oil inlet (19) which is connected with a portion of the hydraulic circuit (15) upstream of the hydraulic motor (8) and for lubricating the drive shaft bearing (13) with fresh hyd rauliköl is formed.

5. Drive device according to one of the preceding claims, wherein the drive shaft bearing (13) has a bearing sleeve (20) within which a coupling sleeve (21) is rotatably mounted, which coupling sleeve (21) rotatably connects the drive shaft (12) to the motor shaft (16) connects.

6. Drive device according to the preceding claim, wherein a log device (22) for sealing the coupling sleeve (21) to the drive shaft (12) is provided and / or the coupling sleeve (21) is connected oil-tight to the drive shaft (12) so that the Coupling sleeve (21) forms a collecting space for hydraulic oil.

7. Drive device according to one of the two preceding claims, where in the case of the bearing sleeve (20) with one end face on the motor housing (17) of the hydraulic motor (8) is connected and / or engages around the motor shaft (16) of the hydraulic motor (8) emerging therefrom .

8. Drive device according to one of the preceding claims, wherein the fresh oil inlet (19) leads into the interior of the bearing sleeve (20) and passes through egg ne wall of the bearing sleeve (20).

9. Drive device according to one of the preceding claims, wherein the bearing sleeve (20) is sealed to the coupling sleeve (21) and / or to the drive shaft (12) by a rotary seal (23) so that an interior of the bearing sleeve (20) forms a collecting space for hydraulic oil .

10. Drive device according to one of the preceding claims, wherein the bearing sleeve (20) at opposite end portions has a hydraulic oil inlet and a hydraulic oil outlet, through which hydraulic oil can be flushed through the bearing sleeve (20).

11. Drive device according to one of the preceding claims, wherein a return of the hydraulic oil passed through the drive shaft bearing (13) into the hydraulic circuit for operating the hydraulic motor (8) is seen before.

12. Drive device according to one of the preceding claims, wherein the bearing sleeve (20) a hydraulic oil collection chamber for lubricating Wälzla like and / or plain bearings through which the drive shaft (12) and / or the coupling sleeve (21) are rotatably supported.

13. Drive device according to one of the preceding claims, wherein the coupling sleeve (21) forms a hydraulic oil collection chamber for lubricating non-rotatable connecting means through which the drive shaft (12) is non-rotatably connected to the motor shaft (16) of the hydraulic motor (8).

14. Drive device according to one of the preceding claims, wherein un below the bearing sleeve (20) and / or the coupling sleeve (21) a collecting space (24) is formed for collecting hydraulic oil.

15. Drive device according to the preceding claim, wherein the Sam melraum (24) is assigned an oil level sensor for detecting the oil level in the Sam melraum (24).

16. Drive device according to one of the two preceding claims, where in the collecting space (24) is assigned a drain for draining oil collected in the collecting space (24), said drain being provided with a releasable closure.

17. Trench wall cutter with a drive device which is designed according to one of the preceding claims.